<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style>
		div{
			width:100px;
			height:100px;
			background:blue;
			
			position:absolute;
			left:500px;

			transition:left 1s linear;
		}
	</style>
</head>
<body>
	<button id="btn">点我运动</button>
	<div></div>

	<script>
		var btn = document.getElementById("btn");
		var div = document.getElementsByTagName("div")[0];

		btn.onclick = function(){
			div.style.left = 0;
		}

	</script>
</body>
</html>